. Bulletin. Insects; Insect pests; Entomology; Insects; Insect pests; Entomology. 48 CEREAL AND FORAGE INSECTS. Table II.—Measurements oflarvx of the sorghum midge. Larva No. 1 2 3. 1 5 Length. Breadth. Milli- Milli- meters. meters. .1804 .082 .28 .082 .329 .12 .493 .141 .573 .25 Larva No. Length. 10. 11. Milli- meters. .89 .903 Breadth. Milli- meters. .35 .35 .492 .5 While the above examinations do not refer to larvae of the same generation, they serve to illustrate the gradual growth from the time of hatching until just before transformation into pupae.
. Bulletin. Insects; Insect pests; Entomology; Insects; Insect pests; Entomology. 48 CEREAL AND FORAGE INSECTS. Table II.—Measurements oflarvx of the sorghum midge. Larva No. 1 2 3. 1 5 Length. Breadth. Milli- Milli- meters. meters. .1804 .082 .28 .082 .329 .12 .493 .141 .573 .25 Larva No. Length. 10. 11. Milli- meters. .89 .903 Breadth. Milli- meters. .35 .35 .492 .5 While the above examinations do not refer to larvae of the same generation, they serve to illustrate the gradual growth from the time of hatching until just before transformation into pupae. These figures can safely be taken as representative of .the measurements of a single larva from date of hatching until full grown. In this instance the larval stage covers eleven days. THE Fig. 26.—The sorghum midge: "Cocooned larvae," the hi- bernating form of the midge. Much enlarged. (Original.) (Fig. 25,/.) When newly formed the pupa is uniformly deep red in color, while just before emergence of the adult the head and appendages turn dark and finally black, while the abdomen remains a deep red. There is often a delicate cocoon surrounding the pupa before the latter has worked its way to the apex of the spikelet for the emergence of the adult. It is evident that such are found upon those pupae derived from " cocooned ; This thin covering is very loosely attached to the pupa and has never been found by the writer after the pupa has left its initial position alongside the ovary. THE " COCOONED ; (Fig. 26.) The "cocooned larva" is closely allied in structure and function to the " flaxseed " of the Hessian fly. The delicate envelope is somewhat elliptical in shape, quite flat, and of a muddy-brown color. It is found close against the ovary itself within the delicate palet. Examined through the microscope the envelope is semitransparent, containing a larva about two-thirds grown and surrounded by a clear p
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